In general, the prior art comprises circuit breakers in which the contact pressure between coactive electrical contact elements, decreases when temperature may be increased. The disadvantages hereof comprise contact chattering and/or excessive arcing. In much of the prior art, there is attempt to create effective latching at the points of contact -- reference Marquis U.S. Pat. No. 3,038,047 dated June 5, 1962, and Desio U.S. Pat. No. 3,234,348 dated Feb. 8, 1966. The circuit breaker of the instant invention, on the other hand, does not involve latching one bimetal to another nor the latching of contacts together. Among the significant patents in this area is the patent to Widmer U.S. Pat. No. 2,915,618, dated Dec. 1, 1959, a thermal time delay switch, directed however to the provision for two bimetal elements extending generally in the same direction in spaced relation to each other together with a heater element, the respective bimetal elements being influenced so as to warp in the same direction, etc.
Other art of interest includes the following, distinguishable on the same and related grounds. Frey et al. U.S. Pat. No. 2,910,561, dated Oct. 27, 1959; Persons U.S. Pat. No. 2,159,342, dated May 23, 1939; Dafler U.S. Pat. No. 3,718,162 dated Feb. 27, 1973; and Brown U.S. Pat. No. 3,702,454 dated Nov. 7, 1972.